種の分布の空間的なパターンは,生物多様性の変化を明らかにします
Robert J Wilson1, Chris D Thomas, Richard Fox
1Centre for Biodiversity and Conservation, School of Biology, University of Leeds, Leeds LS2 9JT, UK. rwilson@escet.urjc.es
Nature
|November 19, 2004
まとめ
生物多様性の変化は,現在の種分布だけで予測できます. 空間的なパターンは,減少している種の範囲が断片化されていることを明らかにし,拡大している種の分布が集約されていることを明らかにし,保全の取り組みを支援しています.
科学分野:
- エコロジー エコロジー エコロジー
- 保護生物学の保護生物学
- バイオジオグラフィー バイオジオグラフィー
背景:
- 世界の生物多様性変化の評価は,ほとんどの種に関する歴史的なデータが限られているため,困難です.
- 種の分布のダイナミクスを理解することは,効果的な保全戦略にとって極めて重要です.
研究 の 目的:
- 現在の種分布パターンが,歴史的な変化 (減少と増加) を推論できることを示す.
- 限られた歴史的情報であっても,空間分布データを用いて,種の脅威レベルを評価する方法を確立する.
主な方法:
- 種の占有率と分布の大きさの空間的パターンを分析する.
- 現在の分布パターンを,イギリス蝶の既知の歴史的な分布変化と相関させる.
- フランドル,ベルギーの蝶種,英国の希少植物種を用いた方法の検証.
主要な成果:
- 減少している種は,希少で断片化された分布を示し,絶滅の過程を示しています.
- 拡大する種は,より密集した,集積された分布を示し,成功した植民地化を反映しています.
- 現在の分布パターンは,英国の蝶の過去の,そしてある程度将来の分布変化を予測することに成功した.
- 分布パターンと変化の関係は,異なる分類種と地理的地域において一貫していた.
結論:
- 現在の空間分布パターンは,生物多様性の歴史的変化に関する貴重な洞察を提供します.
- このアプローチにより,データ不足地域における種の脅威レベルを評価することができます.
- この発見は,地球規模での生物多様性変化のモニタリングと保全計画のための新しいツールを提供します.
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